PGM-FI Alternator on Carb'd 89 accord

[Susanoo]

Will it work? Im in the middle collecting parts for the EFI conversion and i was on the way to my friends house when my current Alt decided to die. I've got a cap in the back for the sub with a voltage readout, with the car on and no lights, 12.3 with the car off and nothing on...12.6. (The cap stays on for a few minutes after the car is off and turns off automatically) I know the PGM-FI Alt has an extra wire...but is this pin simply absent on the Carb Alt? Autozone has two diff part numbers on alternators depending on carb or EFI...help?

[A18A]

yep the carb alternator will work on the efi accord and vice versa

you will have to either swap the plugs for them though (efi is 4 pin, carb is 3 pin) or swap voltage regulators in the alternator. i find the latter easier

[Buzo]

The carb'd ECU needs a signal to tell when the engine is actually running.

So you need to find one terminal in the EFI alternator that is 0V when the ignition key is ON and 12V as soon as the engine fires up.

[carotman]

Like A18A said, just remove the cover and swap the voltage regulator between the two. I tried it more than once and it works fine.

[AccordB20A]

swapping regs is where its at. i run a 3 pin and 4 pin plug on my loom tho in case i blow a reg and i only have a 3 pin as a spare. the 4th wire is not neeeeeded

[Xaisk]

Really easy. Shouldnt take more than 2 minutes. Just swap the reg

[ecogabriel]

Like A18A said, just remove the cover and swap the voltage regulator between the two. I tried it more than once and it works fine.

Ditto

[Dylan464]

hi i did this the other day i put the alternator from my 89 ex carbed 5spd into my 89 ex-i fi auto and when i drove my buddy home at around midnight i noticed all my lights kinda surging so i pulled over and turned everything off heater, sterio, and defrost and watched the lights surging, one of my frineds said its a bad ground but it didnt do it till i changed alternator...are their different amp ratings on them??

i was wondering wt i did wrong i changed the voltage regulator with no problem and my battery light went off but im kinda worried about it cuz im guna lend the car to my mom while i take her jeep camping

plz help much appreciated

[lostforawhile]

The carb'd ECU needs a signal to tell when the engine is actually running.

So you need to find one terminal in the EFI alternator that is 0V when the ignition key is ON and 12V as soon as the engine fires up.

it's very simple I dont know the wire color codes off the top of my head,they are in the electrical book on the wiki, one is 12 volts all the time,one is switched 12 volts and the white/blue wire is to the warning lamp, it's the same on both, the FI alternator has an extra wire for the ecu isn't simply not needed on the carb car

[POS carb]

You can do it, but I'd rather change plugs, your old alt may have a faulty regulator and you won't know until you finish the job and start it up.
I am using a 96 Alternator with a 91 plug
It will charge with only the blk/yel connected!
I went ahead and connected the other two wires anyway

Check your fuses and wiring before you replace this anyway

[lostforawhile]

You can do it, but I'd rather change plugs, your old alt may have a faulty regulator and you won't know until you finish the job and start it up.
I am using a 96 Alternator with a 91 plug
It will charge with only the blk/yel connected!
I went ahead and connected the other two wires anyway

Check your fuses and wiring before you replace this anyway

you need the white/blue because the positive/negative switched signal also operates the warning light,the choke on carb cars, and is a signal to the multifunction module under the dash, and to both the ECu and the carb control box